An assay procedure for single antigens such as Fel d I, Bla g I and Bla g II, using monoclonal antibodies, has been transferred from the absorbance system to a fluorescent system, improving the sensitivity of these tests by several fold. However, recent refinements in an ELISA method, utilizing non-fluorescent detection methods has indicated that this test may also be useful as a method to measure the relative potency of allergenic extracts. Development of these two systems will continue in order to provide statistical limits for each assay. Comparison of these two potency assays to the RAST inhibition method currently employed for release of products will also continue.